For example, in a vehicle-mounted air conditioner, it is necessary to accommodate various components in a limited space in a vehicle, and high space-saving properties are required. Accordingly, in recent years, in order to increase the space-saving properties, an integrated electric compressor has been suggested in which a compressor, a motor for driving the compressor, and a circuit substrate for controlling the motor, which configure the vehicle-mounted air conditioner, are integrally configured. IGBT which is a switching element is mounted on the circuit substrate used in the integrated electric compressor.
In the circuit substrate, an element such as the IGBT is mounted on the substrate body by soldering. For example, Patent Document 1 discloses a printed wiring board in which a bonding stitch portion on a substrate and a plurality of bonding pads are connected by a bonding wire as the circuit substrate. Solder resist or silk is installed on this printed board so that contaminants such as organic solvents leached from soft solder such as solder paste do not flow out to the bonding stitch portion to be bonded.